I Believe My Husband Has Adhd And Would Like To Know How To Approach Him With The Idea?

My husband has ADHD, too. He was fired twice, now he is 42 and waited for 4 months to find a job. If he is fired in the future, I believe that he has no chance to find another job. He is always late, he forgets everything. Once he felt asleep and forgot to pick-up our child from daycare. There is no way to connect with him. He is against everybody's idea, people are accepting us to their houses because I push it so badly, otherwise nobody likes to have a conversation with my husband. He is weird. He spends all the money on the things we really don't need. One day he decides to learn how to ride a bike and go and buy a new bike, the other day he decides to sell lingerie and goes and buys $2000 worth of clothes. When I send him to the grocery store, he doesn't know when to come back, instead he spends 2 hours just to get milk for my son. He is on the pill, doesn't help.
We have a child and I don't know what to do.

I wish it were temporary but it's gotten worse throughout the years. We have two children who are autistic, that alone can be strenuous in any marriage, however, I find myself completely overwhelmed with all things such as housework , making appts or calls, giving the kids the extra attention that they need while all he does is come home and watch T.V. He lost his suit one time! He picked it up from the cleaners and did not know what he did with it. Then he blamed the cleaners that he has been going to for so long. He often interrupted while in conversation with everyone, is extremely disorganized which keeps me overwhelmed in housework. He becomes explosive when he disagrees with something and he usually disagrees with everything, we've been to therapists but it doesn't last. He forgets things he says all the time and denies ever having said it! If he so much as has an idea that I think he has ADHD he will do everything in his power to prove me wrong. I am afraid. I love him but his behavior has been affecting our children. Who will listen to me if I am just the wife of a Lawyer?
P.S. All his friends vanished.